Based on two-degrees-of-freedom (2-DOFs) quarter-car semi-active suspension model, a method for semi-active suspension control is proposed based on immune algorithm. According to this algorithm, an immune controller is designed to research and simulation for semi-active suspension control. Simulation results show that the proposed algorithm is effective，and compared with the passive suspension and fuzzy logic control (FLC) algorithm, its control capability is the best. Using immune controller, the RMS of body vertical acceleration, tire loads and suspension distortion are significantly reduced, so vehicle ride performance, handling stability are effectively improved.

In order to improve the speed control performance of the PMSM(Permanent magnet synchronous motor) vector control system. Utilizing the mathematical model of the PMSM in the dq0 coordinates, and the basic principles of the SVPWM (Space Vector Pulse Width Modulation) control method, a simulation model of the PMSM Space Vector Control System, which contains the double loop of speed and current, has been constructed based on the MATLAB/SIMULINK simulation environment. According to the artificial immune feedback theory and the approximation of the nonlinear function in the immune feedback system, with the help of fuzzy logic, a fuzzy immune PI controller has been made and harnessed in the speed loop. Under the three conditions: steady load startup, speed abrupt change, and load abrupt change, a series of contradistinctive simulation experiments are conducted and compared with the original PI controller respectively. The experimental results showed that the SVPWM control method with the fuzzy immune PI controller can not only make the motor run steadily, but also give it a superior speed performance and torque control characteristics. In addition, the control performance of the fuzzy immune PI controller showed a dramatically improvement compared with that of the traditional PI controller.

In order to improve the vehicles steering performance, based on a whole vehicle dynamics model，the electric power steering system(EPS) control strategy is studied under road surface impact condition. An AIS controller is executed on the output current of assist motor hence further improving control effects. Accompanied the methodology of combining the full vehicle model in CarSim and EPS model in MATLAB, this co-simulation model is verified by test data. By comparison yaw rate and slip angle of the results show that: implementing the control of EPS by AIS compensation strategy is an effective way of enhancing the capability of steering and the stability of operation, which can make it more accurate and flexible.